In the prior art, punch presses each enabling a plurality of tools to be replaced for use are commonly of a turret type. However, with the turret punch press, the types and sizes of tools that can be held on the turret are limited. Accordingly, the turret punch press cannot execute various types of working. Thus, only the measures described below have hitherto been available to improve the functions of the turret punch press.
One of the improved turret punch presses is a multitool type (for example, the Examined Japanese Patent Application Publication (Tokkou-Hei) No. 6-85948). In the multitool turret punch press, one or more of the tools held by the turret are multitools each having a plurality of unit tools. Any of the multitools is indexed and an arbitrary unit tool is then indexed to enable a punching operation.
Another improved turret punch press is a multiturret type (for example, the Japanese Patent No. 2869129). Subturrets are installed on a main turret at a plurality of positions in its circumferential direction so as to be freely rotatively indexed. Tools are arranged on each of the subturrets at a plurality of positions in its circumferential direction.
Further another improved turret punch press is a cartridge type (for example, the Unexamined Japanese Patent Application Publication (Tokkai-Hei) No. 2000-351028). With the cartridge type punch press, a plurality of rectangular cartridges are provided each of which is equipped with a plurality of tools. Each of these cartridges is moved to and away from a punch position on a rail for replacement, the rail constituting a straight path.
In the multitool example, before punching, the entire multitool is lowered until it comes into contact with a surface of a plate material. Subsequently, one of the unit tools is lowered to perform a punching operation. Accordingly, the punching operation may be associated with a combination of an error resulting from the elevating and lowering of the multitool and an error resulting from the elevating and lowering of the unit tool relative to the multitool main body. It is thus difficult to achieve accurate punching.
The multiturret type punch press requires the pivotal indexing of the main turret and the pivotal indexing of one of the subturrets held by the main turret. It is also difficult to accurately achieve these pivotal indexing operations. Furthermore, the size of the entire punch press must be increased.
The center of the turret type cannot be used for a die. Accordingly, the use of a die with a larger diameter is limited.
The cartridge type punch press allows a cartridge to be replaced at a press position by linearly reciprocating the cartridge. Accordingly, if the cartridge is to be replaced with an arbitrary one, then after the old cartridge has been discharged, the desired cartridge must be moved into the press position. This increases the time required to replace the cartridge. Furthermore, any of the tools arranged in the cartridge is indexed by moving a punch driving section on a plane, the punch driving section having a ram. Consequently, the moved portion is heavy, thus making it difficult to quickly index the desired tool. Although some punch presses of this type index the desired tool in one direction by linearly moving the cartridge, they also require the entire cartridge to be linearly moved. Consequently, it is also difficult to achieve quick indexing.
It is an object of the present invention to provide a punch press which enables cartridges to be easily replaced so that the replacement of the cartridges allows the use of a large number of tools, which enables any of the tools in the cartridges to be quickly indexed, and which allows the accuracy of punching to be easily improved.
It is another object of the present invention to enable punching operations such as the formation of larger holes, cutting, forming, and bending.
It is yet another object of the present invention to provide a punch press which enables cartridges to be quickly and easily replaced with desired ones so that the replacement of the cartridges allows the use of a large number of tools, which allows the accuracy of punching to be easily improved, and which can be simply configured.
It is still another object of the present invention to enable punching operations such as the formation of larger holes, cutting, forming, and bending.
It is further another object of the present invention to enable a cartridge to be quickly delivered at a press position and to enable a cartridge held by a cartridge replacing device to be easily replaced at a position different from the press position.
It is further another object of the present invention to enable any of the tools in the cartridges to be quickly indexed and to require only one cartridge rotating mechanism.